Further these expansions result from large-scale gene duplications that took place independently in different sap-eating insects.
Gene duplication is a process that occurs when part of an organism's genetic material is replicated.
Groups of similar genes that share an evolutionary ancestry are called gene families. Given the extensive gene duplication of the amino acid transporter gene families that took place multiple times independently in sap-feeding insects it makes sense that gene duplication might be important for recruiting amino acid transporters to mediate
amino acid exchange between these insects and their symbionts said Rebecca P. Duncan doctoral student in the Department of biology at UM and first author of the study.
However given that the genes expanded independently in each insect sap-feeding insects likely evolved their relationships with their symbionts separately as opposed to in their common ancestor.
To study the historical effects of interactions between genes and between genes and the environment they looked at genes controlling several crop plant traits.
Domestication has yielded modern crops whose seeds resist shattering such as corn whose kernels stay on the cob instead of falling off.
whether genetic factors hindered transmission of genes controlling such traits. Instead they found that domestication traits are passed often faithfully from parent to progeny
#Involvement of gene in lentivirus infections of sheep, goats has been establishedin her Phd thesis Helena Crespo-Otano has studied the mechanism of the action of the small ruminant lentivirus (SRLV) a type of virus
and characterised the ovine MR gene and have determined its involvement in the entry of the virus into the cells that express it.
Plant immunity that is controlled by a single resistance gene on which most conventional breeding programs are based is comparably easy to overcome by a pathogen.
In addition Zurek's team showed that bacteria in the house fly digestive tract can exchange antibiotic resistance by horizontal gene transfer.
We were excited to find that higher calcium intake appears to mitigate the impact of some of the risk genes for type 2 diabetes
Among children who tested positive for gene variants known to be associated with type 2 diabetes those who consumed higher amounts of calcium had a significantly lower body mass index and percent body fat than those with lower
or related dietary factors may cause epigenetic changes that affect how the diabetes-linked genes are expressed.
Understanding the interactions of genes and environmental factors in children is especially helpful for a disease as complex as diabetes said Devaney.
As the result of recent improvements in technology for genetic modification of pigs genes that are immunogenic for humans have been eliminated('knocked out) and several human genes have been added to the pig genome.
Through the combination of a pig heart with certain gene modifications with drugs suppressing both T
The study is published in the April 1 issue of the journal Genes and Development. The first author of the report is Tongde Wu a graduate of the UA Department of Pharmacology
The study Hrd1 suppresses Nrf2-mediated cellular protection during liver cirrhosis is published in the April 1 issue of the journal Genes and Development.
Genes from dwarf birch were found in birch tree populations across Britain which reflects a much wider distribution occupied by the wee tree
As dwarf birch moved north some of its genes were picked up by downy birch trees which spread through Britain at the cost of dwarf birch.
As global warming continues stray genes and fossils could be all that is left of dwarf birch in Britain.
which is used commonly as a farm soil fertilizer contains a surprising number of newly identified antibiotic resistance genes from the cows'gut bacteria.
The findings reported in mbioâ the online open-access journal of the American Society for Microbiology hints that cow manure is a potential source of new types of antibiotic resistance genes that transfer to bacteria in the soils
Thousands of antibiotic resistance (AR) genes have already been identified but the vast majority of them don't pose a problem
when these genes appear in the types of pathogenic bacteria that cause food-borne illnesses
or hospital infections Since there is a connection between AR genes found in environmental bacteria and bacteria in hospitals we wanted to know what kind of bacteria are released into the environment via this route of manure fertilization says Fabienne Wichmann lead study author and former postdoctoral researcher at Yale university in New haven Connecticut.
and they or their genes might move to the human ecosystem. Is this a route for movement of these genes from the barn to the table?
asks Jo Handelsman senior study author and microbiologist at Yale. The first step toward an answer was surveying
which AR genes are present in cow manure. Handelsman's team used a powerful screening-plus-sequencing approach to identify 80 unique and functional AR genes.
The genes made a laboratory strain of Escherichia coli bacteria resistant to one of four types of antibiotics--beta-lactams (like penicillin) aminoglycosides (like kanamycin) tetracycline or chloramphenicol.
Roughly 75%of the 80 AR genes had sequences that were only distantly related to AR genes already discovered.
The team also found an entire new family of AR genes that confer resistance to chloramphenicol antibiotics which are used commonly to treat respiratory infections in livestock.
The diversity of genes we found is remarkable in itself considering the small set of five manure samples says Handelsman who is also a Howard Hughes Medical Institute Professor.
But also these are evolutionarily distant from the genes we already have in the genetic databases
which largely represent AR genes we see in the clinic. That might signal good news that AR genes from cow gut bacteria are not currently causing problems for human patients.
But Wichmann points out another possibility is that cow manure harbors an unprecedented reservoir of AR genes that could be next to move into humans.
This is just the first in a sequence of studies--starting in the barn moving to the soil
and food on the table and then ending up in the clinic--to find out
whether these genes have the potential to move in that direction says Handelsman. AR genes can enter the human ecosystem by two routes--either the bacteria that contain them colonize humans
or the genes are transferred through a process called horizontal gene transfer to other bacteria that colonize humans.
Research has shown already that bacteria are transferred from farm animals to their human caretakers. Gene transfer enables genes to jump between microorganisms that are related not
and it occurs in most environments that host bacteria. Some manure bacteria might be pathogenic to humans
Alternatively benign bacteria in manure might transfer resistance genes to pathogens at any point along the path--in manure soil food or humans.
Olsen on the other hand seeks to identify genes in modern crop species that are associated with domestication traits in the plant such as an erect rather than a sprawling architecture.
The techniques used to isolate these genes are difficult and time consuming and may not always penetrate as deeply into the past as scientists had assumed once
The researchers focused on two genes known to differ between domestic chickens and their wild counterparts:
a gene associated with yellow skin color called BCDO2 and a gene involved in thyroid hormone production called TSHR.
Though the exact function of TSHR is unknown it may be linked to the domestic chicken's ability to lay eggs year-round--a trait that Red Junglefowl
Similarly less than half of the ancient chickens had the version of the TSHR gene found worldwide in modern chickens.
We suspect the seemingly greater tolerance of African bees to these pests over the western bees is a combination of genes and environment.
and indicate long-term gene flow or interbreeding between managed and wild animal populations Marshall said.
These management practices placed only light selection pressure on the herd's gene pool. Paradoxically environmental selection may in many instances have been stronger than artificial selection.
and gene flow highest in the case of pack animals such as donkeys or camelids. But even in the case of pigs or cattle interbreeding between domestic and wild animals has created long and complex evolutionary and domestication histories that challenge assumptions regarding genetic isolation and long-held definitions of domestication.
and the likelihood of long-term gene flow from the wild. It's probably fortunate the Darwin had clear examples of animal breeding to consider as he thought about evolution.
Olsen said favored gene variants (alleles) that are relatively insensitive to background effects and highly responsive to selection.
But finding these alleles in the first place must have said difficult Olsen. Only a subset of the genes in the wild population would have produced reliably a favored trait regardless of the crop variety into
which they were bred and regardless of where that crop was grown. So the early stages of domestication might have been beset by setbacks
Over the past 20 years researchers have begun to identify the genes that control some of the most important domestication traits no easy task in the days before rapid sequencing
because they had to start with plant traits and work back to unknown genes. This work showed that many domestication traits were under the control of single genes.
For example the gene teosinte branched1 (tb1) converts highly branched teosinte plants into single stalks of corn.
But the seeming importance of single genes could have been an artifact of the method used to identify domestication genes which required the researcher to pick candidate genes
and perhaps prematurely narrow the search overlooking indirect genetic effects. Little is known about the underlying genetics of domestication Olsen said.
The new work examines the possibility that two indirect effects--the influence of the genetic background on the expression of a gene (called epistasis)
and the effects of the environment on the expression of genes--might have slowed the selection of plants with the desired traits.
or linked to genes that underlie this trait a major one called QTL 1 and a minor one called QTL2.
In this as in other epistatic interactions the effect of an allele at one location depends on the state of the allele at the other location.
Shattering in plants with a wild green-millet allele at the QTLI location depends on the allele at the QTL2 location.
In contrast shattering in plants with the foxtail-millet allele at QTL1 is unaffected by the allele at the QTL2 location.
In the limited number of examples at their disposal the scientists found it to be generally true that that domesticated alleles were less sensitive to genetic background than wild alleles.
The domestication genes in other words tended to be ones that would produce the same result even if they were introduced into a different crop variety.
When a teosinte plant with a wild tb1 gene is backcrossed repeatedly with maize it produces highly branched plants in uncrowded growing conditions
plants with the domesticated tb1 gene allele are unbranched whether or not they are crowded. Unlike companion-animal breeders early farmers seem to have selected domestication-gene alleles that are insensitive to genetic background and to the environment.
This process would have been slow unrewarding and difficult to understand because the effects of gene variants on the plant weren't stable.
But once sensitive alleles had been replaced with robust ones breeders would have been able to exert strong selection pressure on plant traits shaping them much more easily than before
and the pace of domestication would have picked up. No wonder the archeological record indicates there were false starts failed efforts and long delays.
#Synthetic gene circuits pump up cell signals in study of neurodegenerative diseasessynthetic genetic circuitry created by researchers at Rice university is helping them see for the first time how to regulate cell mechanisms that degrade the misfolded proteins implicated in Parkinson's Huntington
or genes that can increase proteasomal activity she said. This will help us rationally design compounds
The scientists introduced into mice the gene that codes for the normal bank vole prion protein thereby generating mice that express bank vole Prp but not mouse Prp.
Researchers had tried previously to tackle this problem by reducing the quantity of lignin in trees by suppressing genes
but there are ways to ensure that the genes do not spread to the forest. These techniques include growing crops away from native stands
introducing genes to make both the male and female trees or plants sterile; and harvesting trees before they reach reproductive maturity.
When crossing parent plants for example breeders often like to track the genes underlying their trait of interest such as resistance to a pathogen.
That's because pinpointing offspring that carry the right genes is often faster and easier than examining plants for the trait itself.
But sometimes so many genes contribute to a single trait that figuring out which genes are involved in the first place becomes onerous.
This is where Hoekenga thinks his style of research and analysis might one day help. We're trying to describe at the biochemical level what might be responsible for a trait.
The sequences provide researchers access to 96 percent of all peanut genes in their genomic context providing the molecular map needed to more quickly breed drought-and disease-resistant lower-input and higher-yielding
Being able to see the two separate structural elements also will aid future gene marker development-the determination of links between a gene's presence and a physical characteristic of the plant.
#Genes identified that could lead to tough, disease-resistant varieties of riceas Earth's human population marches toward 9 billion the need for hardy new varieties of grain crops has never been greater.
Now researchers at Michigan Technological University have identified a set of genes that could be key to the development of the next generation of super rice.
A meta-data analysis by biologist Ramakrishna Wusirika and Phd student Rafi Shaik has uncovered more than 1000 genes in rice that appear to play key roles in managing its response to two different kinds
Traditionally scientists have believed that different sets of genes regulated plants'responses to biotic and abiotic stress.
However Wusirika and Shaik discovered that 1377 of the approximately 3800 genes involved in rice's stress response played a role in both types stress.
These are the genes we think are involved in the cross talk between biotic and abiotic stesses said Wusirika.
About 70 percent of those master genes are co-expressive--they turn on under both kinds of stress.
The scientists looked at the genes'response to five abiotic stresses--drought heavy metal contamination salt cold and nutrient deprivation--and five biotic stresses--bacteria fungus insect predation weed
A total of 196 genes showed a wide range of expressions to these stresses. The top genes are likely candidates for developing a rice variety with broad stress-range tolerance Wusirika said.
Next they would like to test their findings. We want to do experimental analysis to see if five or 10 of the genes work as predicted he said.
Their study is described in the paper Machine learning Approaches Distinguish Multiple Stress Conditions using Stress-Resposive Genes
and Identify Candidate Genes for Broad Resistance in Rice published in the January edition of Plant Physiology.
Story Source: The above story is provided based on materials by Michigan Technological University. The original article was written by Marcia Goodrich.
what we saw was an inhibition of a marker gene in the lungs after a few weeks indicating an inhibition of metastasis
#Instrument built to study effects of genes, environment on plant traitslet's say plant scientists want to develop new lines of corn that will better tolerate long stretches of hot dry weather.
It contained additional four virulence genes making it extremely invasive and ultimately caused 14 cases resulting in 5 deaths.
and validate genes from the P450 detoxification enzyme superfamily which are expressed highly in the adult females from the area.
The new work reveals that two members of the P450 gene superfamily in particular are expressed highly in resistant Tiassalã mosquitoes:
When these genes were transplanted into Drosophila resistance to pyrethroids and carbamates was generated in otherwise susceptible fly strains..
These genes are familiar candidates to LSTM researchers who have documented previously their links with pyrethroid and DDT resistance.
This new research shows how specific P450 genes can engender resistance across insecticides with entirely different modes of action:
whereas carbamates and organophosphates target the neurotransmitter Acetylcholinesterase encoded by the gene ACE-1. This is where Tiassalã mosquitoes yielded another surprise contributing to their exceptionally high carbamate resistance.
A well-known single nucleotide resistance mutation at the ACE-1 gene is near ubiquitous in the population
but because almost every female is a heterozygote (possesses a resistant and susceptible allele) it did not seem this could cause any variation in resistance.
However from application of a newly-developed qpcr diagnostic it was found that the ACE-1 gene was duplicated in some individuals with those resistant to carbamate much more likely to have duplicated additional copies of the resistant ACE-1 allele.
The genome also revealed the location of genes that may be involved in fighting off pathogens which will help scientists understand more about disease resistance in pines.
and bee distributions LÃ pez-Uribe and colleagues assessed parameters of climate conditions that each of three bee species within the genus Eulaema could tolerate physiologically including temperature and precipitation variability.
By looking at how genes were expressed the molecular biologist narrowed the possibilities from thousands of genes to 608 then to 47 and eventually to three.
These genes are functional in both resistant and susceptible varieties. How they respond to regulations triggered by the fungal infection makes the difference he says.
That's why normal gene cloning didn't work. Resistance to the disease is controlled by the chemical pathways of two growth hormones jasmonate
Two of the three genes are involved directly in the chemical pathways Yen explains. How the third one is involved we still do not know
In the resistant wheat the key resistance gene may delay this chain of reactions until the host tissue is too hard for the disease to develop Yen explains.
and published a revision of the genus Liturgusa in the open access journal Zookeys. Svenson collected the insects from eight countries in Central and South america as well as gathered hundreds of specimens from 25 international museums in North america South america and Europe.
Most of the genes had come from a poultry virus that had existed in china for many years
and two genes probably came from a wild bird isolate he says. We felt a major knowledge gap in the outbreak was that we didn't know which poultry species was maintaining the virus
Some of these earlier studies had traced the genetic origin of this trait in Europeans to a particular mutation that regulates the expression of the gene that codes for lactase.
To look for genetic variations among the populations'abilities to digest milk the team sequenced three genomic regions thought to influence the activity of the lactase-encoding LCT gene in 819 Africans from 63 different populations and 154 non
The research provides a new approach integrating knowledge of genes proteins plant chemical compounds and engineering modeling to understand how plants make products
They analyzed RNA interference (RNAI) a method that uses genetic material to silence specific genes--in this case genes known to give insect pests an advantage.
The team targeted two genes that are regulated differently in rotation-resistant and non-resistant rootworms. The first Dvrs5 codes for an enzyme that helps the rootworms digest plant proteins.
These genes have been found to play a role in rootworm resistance to crop rotation. The team looked at how treatment with RNAI
The researchers were surprised to find that the RNAI targeting the gene att1 had no effect
This does not represent an immediate concern for RNAI technology the researchers said as they tested genes that are unlikely to be used in commercial crops.
The findings suggest that targeting a single gene to control a pest species is not the best strategy Spencer said.
We now know that disrupting a particular target gene may enhance undesirable pest characteristic such as rotation resistance
The researchers identified a de novo gene mutation--one that occurs for the first time in a member of a family--in a gene called GRIN2A.
The discovery required an analysis of the patient's genetic makeup in search of the one gene that changed setting this detrimental series of events in motion.
Pierson added that many other genes have been associated with several forms of epilepsy in infancy but only few other instances of early-onset epileptic encephalopathy involved the GRIN2A gene.
The GRIN2A gene influences electrochemical events that affect the flow and strength of electrical impulses in the brain.
Having identified the de novo gene defect the researchers conducted laboratory experiments to confirm the resulting protein dysfunction and its effects on electrical-regulating mechanisms.
We then performed lab studies with several drugs that were approved already by the Food and Drug Administration and which we thought might block the seizure activity.
Our results suggest that children with early-onset epileptic encephalopathy should undergo evaluation for similar gene variants with the possibility of using memantine
and their ideas--an international postal system organized agriculture research and meritocracy-based civil service among other things--shaped national borders languages cultures and human gene pools
It was shown also that a higher saturated fat intake was associated with an increased risk of dementia among those carrying a genetic risk factor of Alzheimer's disease the epsilon 4 variant of the apolipoprotein E (Apoe) gene.
Most of the yield increases are the result of breeders selecting better combinations of genes that can allow plants to take sunlight and produce more seed from that sunlight.
We don't know what genes breeders are selecting that are resulting in these increases for example where in that pathway from the sunlight hitting the canopy to producing seed where this occurs.
Bt genes have been engineered into a variety of crops to control insect pests. Since farmers began planting Bt crops in 1996 with 70 million hectares planted in the United states in 2012 there have been only three clear-cut cases in agriculture of resistance in caterpillars
To delay or prevent insect pests from evolving resistance to Bt crops the U s. Environmental protection agency promotes the use of multiple Bt genes in plants
and the practice of growing refuges of non-Bt plants that serve as a reservoir for insects with Bt susceptible genes. â#oeour paper argues there is another factor involved:
because they are known to be free of cattle genes and represent bison that existed on the Great plains for thousands of years.
Texas A&m University scientists are working to map the genes controlling drought and heat tolerance in recent varieties.
and ultimately clone the genes controlling drought and heat tolerance for molecular studies and deployment of these genes in other crops she said.
Joining Zhang on the project are Dr. Hongbin Zhang Texas A&m professor of plant genomics and systems biology and director of the Laboratory for Plant Genomics and Molecular genetics;
This research will use high-throughput site-associated DNA sequencing to map the genes controlling drought
and heat tolerant genes but also develop a platform for mapping genes controlling several other biotic and abiotic stress tolerances such as aphid resistance and low phosphorus tolerance both
The drought and heat tolerant genes once defined and cloned will significantly advance understanding of the molecular basis underlying plant tolerances to these stresses Zhang said.
The researchers led by Dr Charles Wondji used a wide range of methods to narrow down how the resistance works finding a single mutation in the GSTE2 gene which makes insects break down DDT
They have shown also that this gene makes insects resistant to pyrethroids raising the concern that GSTE2 gene could protect mosquitoes against the major insecticides used in public health.
The spread of resistance genes could hold back efforts to prevent the disease. The authors say that knowing how resistance works will help to develop tests
and stop these genes from spreading amongst mosquito populations. Charles Wondji said:''We found a population of mosquitoes fully resistant to DDT (no mortality
They identified the GSTE2 gene as being upregulated--producing a lot of protein--in Benin mosquitoes. They found that a single mutation (L119f) changed a non-resistant version of the GSTE2 gene to a DDT resistant version.
They designed a DNA-based diagnostic test for this type of resistance (metabolic resistance) and confirmed that this mutation was found in mosquitoes from other areas of the world with DDT resistance
X-ray crystallography of the protein coded by the gene illustrated exactly how the mutation conferred resistance by opening up the'active site'where DDT molecules bind to the protein so more can be broken down.
They also introduced the gene into fruit flies (Drosophila melanogaster) and found they became resistant to DDT
and later with sugarcane the team introduced genes that boost natural oil production in the plant.
The introduced gene from a South american wild relative of potato triggers the plant's natural defense mechanisms by enabling it to recognize the pathogen.
Cultivated potatoes possess around 750 resistance genes but in most varieties late blight is able to elude them.
and by the time a gene is introduced successfully into a cultivated variety the late blight pathogen may already have evolved the ability to overcome it said Professor Jonathan Jones from The Sainsbury Laboratory.
The Sainsbury Laboratory is continuing to identify multiple blight resistance genes that will difficult for blight to simultaneously overcome.
Their research will allow resistance genes to be prioritized that will be more difficult for the pathogen to evade.
and experiment with multiple resistance genes. By combining understanding of resistance genes with knowledge of the pathogen they hope to develop Desiree
and Maris Piper varieties that can completely thwart attacks from late blight. Story Source: The above story is provided based on materials by Norwich Bioscience Institutes.
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